This is how Endless Space does it, and I hope Stellaris will end up going that route as well.
It was a bit too fiddly in ES for my taste - at least if you are talking about the drop pods that you had to refill manually after use.
Simplification is not a solution. Ground Combat and Army have so much potential!
They do, but always consider the cost at which complexity does come. There is a reason why the current combat system is already more abstract than, let's say, HOI.
My suggestion was less about simplification and more about usability. Remove the over-the-top micromanagement to get armies into position and you can instead focus on making the actual combat more interesting.
Yes, the system has immense potential. For example, we could have air units that zip around in a planet's atmosphere (middle layer), fighting over air superiority and shooting down drop pods as they try to land. We could have planetary artillery and orbital satellite defence networks. Planets could have randomly generated maps where the units auto-move around, fighting over strongholds and key points. We could have an elaborate resistance / guirella warfare system that drags out the actual invasion for decades of ingame time for larger worlds.
However, with the current system that would probably become a bloated mess, making it more complex but not necessarily more fun.
